These model rocket nose cones fit BT-5 body tubes. There are five sets in the package that include a pin for attaching to the nose cone to attach the parachute and the shock cord. There are two styles of nose cone: 3 long, pointed and 2 short, rounded. The long nose cone is 2 inches (5.5 cm) and the shorter nose cone is 3/4 inch (2 cm).